(a) Field
Exemplary embodiments of the invention relate to a liquid crystal display.
(b) Description of the Related Art
A liquid crystal display, which is one of the most widely used type of flat panel displays, typically includes two display panels on which electric field generating electrode, such as a pixel electrode and a common electrode, are disposed, and a liquid crystal layer interposed therebetween. The liquid crystal display displays an image by generating an electric field on a liquid crystal layer by applying a voltage to the electric field generating electrodes, determining alignments of liquid crystal molecules of the liquid crystal layer through the generated electric field, and controlling polarization of incident light.
A liquid crystal display with a vertically aligned mode in which long axes of liquid crystal molecules are arranged to be vertical to upper and lower display panels in a state where an electric field is not applied among the liquid crystal displays may have a high contrast ratio and a wide reference viewing angle.
In a vertical alignment mode liquid crystal display, a plurality of domains having different alignment directions of liquid crystal may be provided in each pixel to implement a wide viewing angle.
One example of a method of providing the plurality of domains is a method of forming a cutout, such as a slit, in an electric field generating electrode. In such a method, the liquid crystal is rearranged by a fringe field generated between an edge of the cutout portion and an electric field generating electrode facing the edge, such that the plurality of domains may be formed.
An example of the liquid crystal display including domains in each pixel thereof includes a vertical alignment (“VA”) mode liquid crystal display including the domain forming element provided at both upper and lower substrates, and a patternless VA, in which a micro-pattern is formed at only a lower substrate, and a pattern is not formed at an upper substrate. In such a liquid crystal display, a display area is divided into a plurality of domains by the domain forming elements, and liquid crystal within each domain is substantially inclined in the same direction.
Recently, an initial alignment method, in which liquid crystal has pretilt in a state where an electric field is not applied, has been suggested to increase a response speed of liquid crystal while implementing a wide viewing angle. In the initial alignment method, an alignment layer in which alignment directions are plural is used, or an alignment supplement agent for making the liquid crystal to have the pretilt is added to the liquid crystal layer, an electric field is applied to the liquid crystal layer, and then the alignment supplement agent is hardened, to allow the liquid crystal to have the pretilt in various directions. The alignment supplement agent hardened by light, such as heat or ultraviolet rays, may allow the liquid crystal to have a pretilt in a specific direction. In the initial alignment method, a voltage is applied to each of the electric field generating electrodes to generate the electric field in the liquid crystal layer.
However, the alignment supplement agent, an ultraviolet ray hardening process, and the like are typically used to manufactured the liquid crystal display including the alignment supplement agent for the pretilt, such that a new process line is required and a manufacturing cost increases.